Petrobras, Brazil’s state-controlled oil and gas multinational is the world’s eighth biggest global company in market value, according to a survey carried out by London-based professional services firm Ernst & Young.

The study was based on the companies’ stock value in the end of the first half of the year and shows the recovery of Petrobras’ stock after the most critical moment of the global financial crisis, in 2008. Petrobras is among top ten outfits that appreciated the most in the world in the first half of the year.

Petrobras’ market value soared from US$ 95.9 billion to US$ 164.8 billion, allowing the Company to surge from the 37th place to the eighth place in the ranking of the world’s biggest corporations.

Only three Brazilian companies made the survey’s list of the 100 biggest. Together, the three had the biggest appreciation, with an increase of 101%, a percentage well above that of the Russian companies, which accumulated 42% and scored second.

In the United States, Petrobras’ stock is traded on the New York Stock exchange as ADRs. In the first half of 2009, the ADRs appreciated approximately 67% and 64% for the PBR (common stock) and PBRA (preferred stock) receipts, respectively.